There has been known an inkjet head that uses shear deformation of a piezoelectric member to eject ink drops from nozzles. Such an inkjet head is a so-called shared-wall-type inkjet head and mainly used in an inkjet printer. The shared-wall-type inkjet head enables so-called multi-drop gradation printing by effecting control so that one or more ink drops can be ejected from the nozzles in accordance with a gradation.
However, the shared-wall-type inkjet head has a problem that volumes of ink drops ejected from the nozzles differ and high-quality printing cannot be carried out when the gradation printing is performed.